Jaw breaker



July 5, 1938. MIEISTER 2,123,017

JAW BREAK-ER Filed Aug; 2, 1935 Patented July 5, 1938 UNITED STATES PATENT OFFICE JAW BREAKER Karl Meister, Magdeburg, Germany, assignor to the flrm Fried. Krupp Grusonwerk Aktiengesellschaft, Magdeburg-Buckau, Germany Germany September 1, 1934 Application August 2, 1935, Serial No. 34,459

1 Claim. (Cl. 83-53) My invention relates to a jaw breaker, the jaws of which lie one over the other and form an obliquely extending breaking gap, the arrangement being such that the lower jaw alone, or 5 both jaws, are adapted to be moved. In all law breakers, capable of disintegration of the material in a progressive manner-the breaking gap becomes narrower towardsthe mouth of the jaws and the quantity of crushed material passing in therethrough becomes greater. Consequently, a constant overloading of the lower breaking zones occurs. In order to avoid this overloading, it has already been proposed to widen the breaking jaws in the direction of the mouth or delivery gap. 16 This step, however, is in practice ineffective because the material only follows the surface of the widened portions within certain limits. It has also already been proposed to accelerate the passage of the disintegrated material by producing 5 a projecting movement in the lower breaking gap to avoid the. overloading of the lower breaking zones. This step, however, is contingent upon the material being charged in a grain size corresponding approximately to the width of the upper 25 gap of the breaker.

The object of the present invention is to produce a jaw breaker with which over-stressing in .the lower breaking zones and damming of the material to be broken are obviated, and with this 30 object in view, according to the invention the inclination of the breaking surface of the lower breaking jaw is increased in the direction of the delivery gap. In this case, the form of the breaking jaw is of minor importance but the clamping I6 angle between the two breaking jaws must be made such that the material to be broken does not jump upwards out of the breaking mouth during the breaking operation. It is preferable to adapt the upper breakingjaw to the lower breaking jaw as far as possible by giving it an inwardly curved form- The upper surface of the lower breaking jaw may, for example, be so shaped that the upper surface extends evenly or practically evenly at a small angle with respect to the horizontal, then falls in a slight curve and finally again falls away evenly or substantially evenly at a steeper angle.

However, the entire surface may be made in w arched form without departing from the scope of the invention.

In order that the said invention may be clearly understood and readily carried into effect, the

same will now be described more fully with reference to the accompanying drawing which illustrates a breaker constructed according to the .invention, in vertical section.

The upper breaking jaw 2 is secured to the frame I of the breaker, and beneath this upper jaw 2 the lower breaking jaw 3 is mounted in a 5 rocking member 4. This rocking member may be mounted and driven in various ways known per se. It may, for example, be adapted to pivot at its upper end about a shaft 5 rigidly mounted in the breaker frame, whilst the lower end may be moved in an upward and downward direction by means of an eccentric drive 6. As a further example, the rocking member could also be mounted at its lower end on a support and be driven at its upper end by an eccentric carried by a driving shaft. ,According'to the invention, the breaking surface of the jaw 3 is increasingly inclined in the direction of the delivery gap, this surface extending at a small angle relatively to the horizontal from a to b, but then merging. from b to 0 into a slight downwardly bent curve the curve extending downwardly more steeply from M.

The surface of the upper breaking jaw .2 is curved inwardly to correspond to the curvature of the lower breaking jaw. However, it could, for example, also extend evenly. The inclination of the breaking surface of the upper jaw is preferably such that at the entrance of the breaking space a further gap is formed which to a certain extent forms an extension of the charging hopper.

The material to be broken may be charged into the filling hopper l of the breaker in unlimited quantities, i. e. the hopper may always be completely filled without fear of over-stressing the breaking jaws. Owing to the hereinbefore described formation of the breaking jaw 3, the material to be crushed is, in the upper part of the breaking jaw where it lies on a slightly inclined surface, at first retained somewhat and is only conveyed slowly towards the delivery gap. As, consequently, the material remains longer than usual in the upper breaking space, a much better utilization of the breaker results in this breaking zone.

The material already sufllciently crushed in the upper breaking mouth is only conveyed forward with increasing speed in proportion with the progressive crushing, so that the quantity of 5 crushed material and the conveyance of the material in all zones of the breaking mouth are substantially adapted to one another. ,The breaker consequently works in a completely uniform manner in all its breaking zones, and is not subjected delivery gap may be imparted to the material.

The material to be broken will thus, between two strokes, travel over a path which is in any case greater than the path over which it would travel in the breaking gap merely owing to the force of gravity. The magnitude of the movement of the material in the direction of the delivery gap,

however, is also dependent on the form. of the breaking mouth, this movement being greater as the breaking surface repelling the material is steeper. According to the present invention, the increase of speed for this movement towards the delivery gap is so considerable owing to the increasing inclination of the breaking surface of the lower breaking jaw that a strong projecting movement and consequently a considerable freeing from load of the breaking mouth is produced in the lower zone. This movement of projection will not be set up in the upper part of the break ing gap owing to the sllghter inclination of this part of the breaking surface, but the material on this part of the breaking surface will only be moved forward slightly and at the same time intensely broken, so that the breaker can work without any special quantitative apportioning of the material, that is to say, with a completely above the upper end of said lower jaw, said lower jaw having a receiving surface below said hopper inclined very slightly toward the discharge end of said jaws, the crushing face of said lower jaw having a generally convex surface joined to the lower end of said receiving surface and sloping downward therefrom, first at an inclination just enough greater than the inclination of said receiving area to feed the material thereon at a slightly greater speed, and then with a gradually increasing inclination toward the discharge end of said jaws, said upper jaw having a crushing face inclined somewhat more steeply than the average inclination of the face of said lower law, so as to form a gap of gradually diminishing size toward the discharge end, the upper end of said gap being of suitable size to cause the larger lumps to be crushed in the upper end of the gap, and the shape of said gap and the gradually increasing inclination of the face of said lower jaw being so related that the material is crushed progressively as it moves down the gap and the quantity of crushed material and the conveyance of the material in all zones of the gap are substantially adapted to one another.

KARL MEISTER. 

